Selecting versions of CICS programs and tables

A CICS® program is usually made up from a group of related CICS functional modules, one example of which is the terminal control program. For most CICS programs you can only have one version, which is supplied with CICS. However, for some CICS programs you can create more than one version; for example, with different service levels.

To select a particular version of a program, you can include the load library containing that version in the CICS startup JCL. For the basic mapping support (BMS) suite, however, you can select from different versions, by explicitly selecting the level of function needed.

You can also specify that a program is not needed.

You can use these methods only for the programs referred to in this topic by coding system initialization parameters.

Using an explicit level of function to select programs

You use an explicit level of function to select the BMS suite of programs. When you specify your BMS requirement on the system initialization parameter BMS, you can select one of three versions. The BMS level of function is selected by the parameter options MINIMUM, STANDARD, or FULL, from which the system initialization program loads the set of programs you require.

Excluding unwanted programs

There are three ways to exclude programs that are not required. You can exclude programs by specifying:
  1. programname=NO
  2. tablename=NO
  3. function=NO
programname=NO
If you code system initialization parameter programname=NO (for example, DIP=NO), you exclude the named management program at CICS system initialization. You can exclude the following programs by coding programname=NO:
  • Batch data interchange program (DIP)
  • Terminal control program (TCP)
Note: In the case of DIP, you get a dummy version of the management program, which is supplied on the distribution tape with a suffix of DY.
tablename=NO
You can specify tablename=NO for the programs control table. Not all of the CICS programs have a programname parameter in the SIT.
A system initialization parameter alternative method is to code NO on the for the associated table. This has the same effect as coding NO against a program name parameter, and the associated CICS program is excluded at system initialization, either by loading a dummy program, or by some other technique.
The system recovery table (SRT) can be used in this way, and the associated system recovery program (SRP) will be excluded.
Note: The dummy TCT, DFHTCTDY

There is a special case where you can also specify tablename=NO, but this does not load a dummy terminal control program. You specify TCT=NO when you are using resource definition online, and all your terminal resource definitions are in the CICS system definition file (CSD).

When you specify TCT=NO, CICS loads a dummy TCT named DFHTCTDY. A pregenerated dummy table of this name is supplied in .SDFHLOAD, and the source statements of DFHTCTDY are supplied in .SDFHSAMP. If you specify TCT=NO, a generated table of this name must be available in a library of the DFHRPL concatenation when you start CICS.

The dummy TCT provides only the CICS and z/OS® Communications Server control blocks that you need if you are using z/OS Communications Server terminals and using the CSD for storing terminal definitions. You define your z/OS Communications Server terminals using the RDO transaction, CEDA, or the DEFINE command of the CSD update batch utility program DFHCSDUP.

function=NO
If you code function=NO as a system initialization parameter, you exclude the management program associated with the named function at CICS system initialization. You can exclude functions such as intersystem communication (ISC), the 3270 print-request facility, and the system spooling interface in this way.